Passage 1: “There are two types of such cells: one is very sensitive to light, the other less so. The more sensitive cells record only in black and white; the less sensitive cells record in color. If we look around the animal world, we can assess whether animals are specialized for daylight or night by looking at the percentages of each type of light-sensing cell in their eyes.” (page 150)
Enduring Understanding: 1.A: Change in the genetic makeup of a population over time is evolution.
Explanation: It’s only necessary for an animal to see color if they’re usually out at day so if they’re usually out at night their eyes only see in the dark. It makes no sense for this …show more content…
This shift happened when the descendants of fish began to walk on land. Hearing in water is different from hearing on land, and the small size and position of the stapes makes it ideal for picking up vibrations in air. The new ability came about by modifying the upper jawbone of a fish.” (page 164)
Enduring Understanding: 2.D – Growth and dynamic homeostasis of a biological system are influenced by changes in the system’s environment.
Explanation: We are structured a certain way to help us live our environment. Our environment is an important deciding factor on how we grow and how each organ in or out our body grows. Our stapes bone in our ear for example is smaller than the hyomandibula so we can hear clearer on land (where we live) than on water. This shows how once our bodies get used to our environment, it shapes itself to adjust to the world around us.
Big Idea 3: Living systems store, retrieve, transmit, and respond to information essential to life …show more content…
The bumps, puts, and ridges on teeth often reflect the diet. Carnivores, such as cats, have blade-like molars to cut meat, while plant eaters have a mouth full of flatter teeth that can macerate leaves and nuts.” (page 60)
Enduring Understanding: 4.A – Interactions within biological systems lead to complex properties.
Explanation: Animals who only eat meat, like cats, have sharper teeth than animals who only eat plants because it helps them eat what they were made to eat. If cats had flat teeth like herbivores, they wouldn’t be able to eat their meat and they would die. As stated in natural selection, the most fit survive so each living thing has teeth sharp or dull enough to help them survive through their life and differences in location give differences in teeth.
Passage 2: “Collagen requires a relatively large amount of oxygen for its synthesis and would have greatly increased our ancestors’ need for this important metabolic element. But the problem was this: levels of oxygen on the ancient earth were very low. For billions of years oxygen levels in the atmosphere did not come close to what we have today. Then, roughly a billion years ago, the amount of oxygen increased dramatically and has stayed relatively high ever since.” (page